It is common practice to package many items, particularly dairy food items, in plastic containers in the form of cups or tubs having a sealing lid thereon. The lid is associated with the container in such manner that the lid can be removed for removal of some or all of the contents of the container. In the event that all of the contents are not removed, then the lid is capable of being reinstalled on the container for storage of the contents.
Unfortunately, some shoppers are quite inconsiderate of the rights of other shoppers and of the store in which goods are sold. Some shoppers will remove the lid of the container to smell or sample the contents, and then replace the lid on the container and return the container to its sale position. Such opening and reclosing of the container, particularly if a part of the contents is removed, raises a serious question of contamination of the contents, and also may result in short weight being given to the ultimate consumer. If sufficient of the contents has been removed a subsequent would be purchaser is likely to notice the short weight, but customers are not accustomed to having to estimate by weight whether a container is full, and customers should not have to do this.
Accordingly, various efforts have been made to produce a more or less tamper proof container assembly. Some such efforts have involved the adhering or welding of container and lid together. This is undesirable in that it requires special and expensive machinery for securing the parts together. Furthermore, opening of such packages can be difficult and may result in tearing of a portion of a container, thereby rendering it essentially useless for subsequent storage. Other efforts to produce tamper proof containers have produced inter-engageable parts of containers and lids which overlap to the point that the lid cannot be properly engaged for removal without first tearing off a portion of the inter-engageable structure. With a portion so torn off a simple visual inspection reveals that there has been tapering with the container.